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Places > the one serving to carry him into his Harbour, the other to bring him out. But I should go too far to take notice of all Particulars (/). Leaving therefore the Winds, I proceed in the next Place to the Clouds and Rain.
Comparison. In half an hours Time after it has reached the Shore, it fans pretty briskly, and so encreafeth gradually till tivelve a Clock; then it is commonly strongest, and lasts so till two or three, a very brisk Gale. — After three it begins to die away again, and gradually withdraws its force till all is spent; and about five a Clock —— it is lulled asteep, and comes no more till next Morning.
And as the Sea Breezes do blow in the Day, and rest in the Night; so on the contrary [The Land-Breezes] blow in the Night, and rest in the Day, alternately succeeding each other.
They spring up between six and twelve at Night, and last
till fix, eight, or ten in the Morning. Dampier'* Disc. o£ Winds, ch. 4.
(f) One Thing more I believe some of my Friends will expect from me is, that 1 shew the Result of comparing my own Observations of the Winds, with others they know I have from Ireland, Switzerland, Italy, France, New-England» and some of our Parts of England. But the Observations being some of them but of one Year, and most of the rest of but a few Years, 1 have not been able to determine any great Matters. The chief of what I have observed i?, that the Winds in all these Places seldom agree, but when they most certainly do so, it is commonly when the Winds are strong, and of long continuance in the fame Quarter: And more I think in the Northerly and Easterly, than other Points. Also a strong Wind in one Place, is oftentimes a weak one in another Place, or moderate, according as Places have been nearer or farther distant. Vid. Phil. Trans. N°. 297, and 3ir. But to give a good and tolerable Account of this or any other of the Weather, it is necessary to have good Histories thereof from all Parts; which, as yet we have but few of, and they imperfect, for want of longer and sufficient Observations.
Ci CHAP. CHAP. III.
Os the Clouds and Rain.
TH E Clouds and Rain (a) we shall find to be no less useful Meteors than the last mentioned; as is manifest in the refreshing pleasant Shades which the Clouds afford, and the fertile Dews and Showers which they pour down on the Trees and
(a) Clouds and Rain are made of Vapours raised from Water, or Moisture only. So that I utterly exclude the Notion of Dry, Terrene Exhalations, or Fumes, talked much of by most Philosophers; Fumes being really no other than the humid Parts of Bodies respectively Dry.
These Vapours are demonstratively no other than small Bubbles, or Vesiculæ detached from the Waters by the Power of the Solar, or Subterraneous Heat, or both. Of which fee Eook z. Chap. 5. Note (b). And being lighter than the Atmosphere, are buoyed up thereby, until they become of an equal Weight therewith, in some of its Regions aloft in the Air, or nearer the Earth; in which those Vapours are formed into Clouds, Rain, Snow, Hail, Lightning, Dew, Mists, and other Meteors.
In this Formation of Meteors the grand Agent is Cold, which commonly, if not always, occupies the superior Regions of the Air; as is manifest from those Mountains which exalt their lofty Tops into the upper and middle Regions, and are always covered with Snow and Ice.
This Cold, if it approaches near the Earth, presently precipitates the Vapours, either in Dews; or if the Vapours more copiously ascend, and soon meet the Cold, they are then condensed into Misting, or else into Showers of small Rain, falling in numerous, thick, small Drops: But if those Vapours are not only copious, but also as heavy as our lower Air it self, (by means their Bladders are thick and fuller..of Water,) in this Cafe they become visible, swim but a little Height above the Earth, and make what we call a Mist or Wat, But if they are a Degree lighter, so as to mount higher, but not any great Height, as also meet not with Cold enough to condense them, nor Wind to dissipate them, they then form an heavy, thick, dark Sky, lasting oftentimes for several Week9 ~- """' without
Plants, which would languish and die with perpetual Drought, but are hereby made Verdant and Flourishing, Gay and Ornamental ; so that fas the
without either Sun or Rain. And in this Cafe, I have scarce ever known it to Rain, till it hath been first Fair, and then foul. And Mr. Clarke, (an ingenious Clergyman of Norfolk, who in his Life-time, long before me, took notice of it, and kept a Register of the Weather for thirty Years, which his learned Grandson, Dr. Samuel Clarke put into my Hands, he, I fay) faith, he scarce ever observed the Rule to fail in.all that Time; only he adds, If the Wind be in some of the easterly Points. But I have observed the same to happen, be the Wind where it will. And from what hath been said, the Case is easily accounted for, viz. whilst the Vapours remain in the fame State, the Weather doth so too. And such Weather is generally attended with moderate Warmth, and with little or no Wind to disturb the Vapours, and an heavy Atmosphere to support them, the Barometer being commonly high then. But when the Cold approaches, and by condensing drives the Vapours into Clouds or Drops, then is way made for the Sun-beams, till the fame Vapours, being by further Condensation formed into Rain, fall down in Drops.
The Cold's approaching the Vapour?, and consequently the Alteration of such dark Weather I have beforehand perceived, by some few small Drops of Rain, Hail, or Snow, now and then falling, before any Alteration hath been in the Weather; which I take to be from the Cold meeting some of the straggling Vapours, or the uppermost of them, and condensing them into Drops, before it arrives unto, and exerts it self upon the main Body of Vapours below.
1 have more largely than ordinary insisted upon this part of the Weather, partly, as being somewhat out of the way; but chiefly, because it gives Light to many other Phenomena of the Weather. Particularly we may hence discover the Original of Clouds, Rain, Hail and Snow; that they are Vapours carried aloft by the Gravity of the Air, which meeting together so as to make a Fog above, they thereby form a Cloud . If the Cold condenseth them into Drops, they then fall in Rain, if the Cold be not intense enough to freeze them: But if the Cold frcezeth them in the Clouds, or in their Fall through the Air, they, then become Hail or Snow.
As to Lightning, and other enkindled Vapours, 1 need fay
little in this Place, and Ihall therefore only observe, that they
owe also their Rife to Vapours; but such Vapours as are de»
C 3 tached
/ %% . Of the Clouds and Rain. Book I.
Psalmist faith, Pfal. lxv. 12,13.) The little Hills rejoice on every side, and the Falleys Jhout for Joy^ they altffing. 'And,
tached from mineral Juices, or at least that are mingled with them, and are fired by Fermentation.
Another ■ Phenomenon resolvable from what hath been said is, why a cold, is always a wet Summer, viz., because the Vapours rising plentifully then, are by the Cold soon collected into Rain. A remarkable Instance of this we had in the Summer of 1708, part of which, especially about the Solstice, was much colder than usually. On June n, it was so cold, that my Thermometer was near the Point of hoar Frost, and in some Places I heard there was an hoar Frost; and during all tlie cool Weather of that Month, we had frequent and large Rains, so that the whole Month's Rain amounted to above two Inches Depth, which is a large Quantity for Upminstcr, even in the wettest Months. And not only with us at upminfier, but in other Places, particularly at Zurich in Switzerland, they seem to have had as unseasonable Cold and Wet as
we. Fuit hie mensts pr&ter modum humidus, cy magno
auidem vegetabdibus hominibufque damno. Mult urn comfutrutt Fœnum, 6cc. complains the industrious and learned Dr. J. y. Scheuchz.er: Of which, and other Particulars, I have given a larger Account in Phil. Trans. N°. 311.
In which Transaction I have observed, farther, that about the Equinoxes we (at Upminster&t least) have oftentimes more Rain than at other Seasons. The Reason of which is manifest from what hath been said, viz.. in Spring, when the Earth and Waters are loosed from the brumal Constipations, the Vapours arise in great Plenty: And the like they do in Autumn, when the Summer Heats, that both dissipated them, and warmed the superior Regions, are abated; and then the Cold of the superior Regions meeting them, condenseth them into Showers, more plentifully than at other Seasons, when either the Vapours are fewer, tor the Cold that is to condense them is less.
The manner how Vapours are precipitated by the Cold, or reduced into Drops, I conceive to be thus: Vapours being, as I said, no other than inflated VesicuU of Water; when they meet with a colder Ait than what is contained in them, the contained Air is reduced into a less Space, and the watery Shell or Cafe rendered thicker by that means, so as to become heavier than the Air, by which they are buoyed up, and consequently must needs fall down. Also many of those
And, if to these Uses, we should add the Ori
gine of Fountains and Rivers, to Vapours and the
thickned VesicuU run into one, and so form Drops, greater or smaller, according to the Quantity of Vapours collected together.
As to the Rain of ,'different Places, I have in some of our Transactions assigned the Quantities; particularly in the last cited Transaction, I have assigned these, viz,, the Depth of the Rain one Year with another, in English Measure, it it was to stagnate on the Earth, would amount unto, at Townely in Lancashire, 42-f Inches; at Upminsler in Essex 19-^- Inches; at Zurich in Switzerland 32 i Inches; at Pisa in Italy 43 i Inches; at Paris in trance 19 Inches; and at Lisle in slanders 24 Inches.
It would be endless to reckon up the bloody and other prodigious Rains taken notice of by Historians, and other Authors, as præternatural and ominous Accidents; but, if strictly pried into, will be found owing to natural Causes: Of which, for the Reader's Satisfaction, I will give an Instance or two. A bloody Rain was imagined to have fallen in Trance, which put the Country People into so great a Fright, that they left their Work in the Fields, and in great haste flew to the Neighbouring Houses. Peirisc (then in the Neighbourhood) strictly enquiring into the Cause, found it to be only red Drops coming from a fort of Butterfly that flew about in great Numbers at that Time, as he concluded from feeing such red Drops come from them; and because these Drops were laid, Nc» supra tdificia, non in devexis lapidum superficiebus, uti debuerat contingere, ft e coelo sanguinepluisj'et; sedin subcavis potiui z? in soraminibus.—^— Accessit, quod parietes Us tingebantur, non qui in mediis oppidis, Jed qui agrorum vicini erant, neque secundum parses elatiores, fed ad mediocrem filum altitudinem, quantum iiolitart Papiliones sclent. Gaflend in vit. Peiresk. L. 2. p. 156.
So Dr. Merret faith also, Pluvia Sanguinis quamcertiffime confiat esse tantum Insetlorum excrementa: Pluvia Triplet quam nihil aliud esse quam Hedert baccisert grana a Sturnis devorata excretaque comparanti liquidispmepatet. Pinax rerum, zrc. p. 220.
The curious Wer/w tells of the raining of Brimstone, An. 1646. Mail 16. Hie Has nit cum ingenti pluvia tot a urbs, omnesque it a inundarentur platee, ut gresjus hominum impediret, Sulphureoque cdore a'erem inficeret, dilapfis aliquantulum aquis, quibujdam in locis colllgere licuit Sulphureum pulverem, cujus portionem servo, colore, odore, & aliis verum Sulphur serentem. Mus. Worm. h. i. c. 11, Sect. 1.
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